• Journal of the Korean Geosynthetics Society
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• v.20 no.4
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• pp.33-41
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• 2021

Feldspar, along with Quartz, are the most frequently produced minerals in Korea; however, the potential value is estimated to be significantly low because of the scarce research on the development and application of material properties, except for their limited use in manufacturing minerals, glass, and paints. In this study, we analyzed the eco-friendly material and reactivity improvement characteristics of weathered feldspar through activation technique. The joint structural features observed on the surface of the weathered feldspar show that the joint arrangements are irregularly distributed, and the cavities are interconnected. Due to the irregularly connected cavities on the surface of weathered feldspar, the reaction area of the weathered feldspar is increased; hence the weathered feldspar is considered as a highly reactive pozzolan material when combined with cement. As a result of applying the thermal, mechanical, and chemical activation techniques to improve the functionality of the weathered feldspar, the cation exchange capacity, density, and uniaxial compression strength characteristics were improved. It is considered that weathered feldspar by these porous characteristics can be used as an eco-friendly construction material with excellent physical and chemical properties.

• Journal of Practical Agriculture & Fisheries Research
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• v.22 no.1
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• pp.35-42
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• 2020

This study was conducted to investigate the photosystem II activities of Cercis chinensis by soil water condition. Drought stress was induced by withholding water and waterlogging treatments was immerging the pots for 15 days. Results showed that the relative activities per reaction center such as ABS/RC, TRo/RC and Dio/RC were significantly increased compared with the control group after 12 days in waterlogging treatments. Particularly, Dio/RC increased substantially under waterlogging stress, indicating that excessive energy was consumed by heat dissipation. Furthermore, the performance index on absorption basis(PI_abs) and responses to structural and functional PS II(SFI_abs) were dramatically decreased after 15 days in both the drought and waterlogging treatments, which reflects the relative reduction state of the photosystem II. These results of chlorophyll a fluorescence by OKJIP analysis show that the sensitive changes photosystem II activity. Thus, on the basis of our results that Cercis chinensis was exhibited a strong reduction of photosynthetic activity to waterlogging stress, and OKJIP parameters such as ABS/RC, DIo/RC, PI_abs and SFI_abs could be useful indicator to monitor the physiological states of Cercis chinensis under soil water condition.

• Nuclear Engineering and Technology
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• v.54 no.3
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• pp.959-964
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• 2022

Lead is an important material, both for fusion or fission reactors. The cross sections of natural lead should be validated because lead is a main component of lithium-lead modules suggested for fusion power plants and it directly affects the crucial variable, tritium breeding ratio. The presented study discusses a validation of the lead transport libraries by dint of the activation of carefully selected activation samples. The high emission standard ²⁵²Cf neutron source was used as a neutron source for the presented validation experiment. In the irradiation setup, the samples were placed behind 5 and 10 cm of the lead material. Samples were measured using a gamma spectrometry to infer the reaction rate and compared with MCNP6 calculations using ENDF/B-VIII.0 lead cross sections. The experiment used validated IRDFF-II dosimetric reactions to validate lead cross sections, namely ¹⁹⁷Au(n, 2n)¹⁹⁶Au, ⁵⁸Ni(n,p)⁵⁸Co, ⁹³Nb(n, 2n)^92mNb, ¹¹⁵In(n,n')^115mIn, ¹¹⁵In(n,γ)^116mIn, ¹⁹⁷Au(n,γ)¹⁹⁸Au and ⁶³Cu(n,γ)⁶⁴Cu reactions. The threshold reactions agree reasonably with calculations; however, the experimental data suggests a higher thermal neutron flux behind lead bricks. The paper also suggests ²⁵²Cf isotropic source as a valuable tool for validation of some cross-sections important for fusion applications, i.e. reactions on structural materials, e.g. Cu, Pb, etc.

• Journal of Korean Neurosurgical Society
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• v.65 no.5
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• pp.680-687
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• 2022

Objective : The influence of moderate-to-severe traumatic brain injury (TBI) on acute pulmonary injury is well established, but the association between acute pulmonary injury and mild TBI has not been well studied. Here, we evaluated the histological changes and fluctuations in inflammatory markers in the lungs to determine whether an acute pulmonary inflammatory response occurred after mild TBI. Methods : Mouse models of mild TBI (n=24) were induced via open-head injuries using a stereotaxic impactor. The brain and lungs were examined 6, 24, and 72 hours after injury and compared to sham-operated controls (n=24). Fluoro-Jade B staining and Astra blue and hematoxylin staining were performed to assess cerebral neuronal degeneration and pulmonary histological architecture. Quantitative real-time polymerase chain reaction analysis was done to measure inflammatory cytokines. Results : Increased neuronal degeneration and the mRNA expression of interleukin (IL)-6, tumor necrosis factor (TNF)-α, IL-10, and transforming growth factor (TGF)-β were observed after mild TBI. The IL-6, TNF-α, and TGF-β levels in mice with mild TBI were significantly different compared to those of sham-operated mice 24 hours after injury, and this was more pronounced at 72 hours. Mild TBI induced acute pulmonary interstitial edema with cell infiltration and alveolar morphological changes. In particular, a significant infiltration of mast cells was observed. Among the inflammatory cytokines, TNF-α was significantly increased in the lungs at 6 hours, but there was no significant difference 24 and 72 hours after injury. Conclusion : Mild TBI induced acute pulmonary interstitial inflammation and alveolar structural changes, which are likely to worsen the patient's prognosis.

• Fisheries and Aquatic Sciences
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• v.26 no.3
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• pp.188-203
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• 2023

Lysozymes are well-known antibacterial enzymes that mainly target the peptidoglycan layer of the bacterial cell wall. Animal lysozymes are mainly categorized as g-type, c-type, and i-type based on protein sequence and structural differences. In this study, c-type (AcLysC) and g-like-type (AcLysG-like) lysozymes from Amphiprion clarkii were characterized in silico via expressional and functional approaches. According to in silico analysis, open reading frames of AcLysC and AcLysG-like were 429 bp and 570 bp, respectively, encoding the corresponding polypeptide chains with 142 and 189 amino acids. Elevated expression levels of AcLysC and AcLysG-like were observed in the liver and the heart tissues, respectively, as evidenced by quantitative real-time polymerase chain reaction assays. AcLysC and AcLysG-like transcript levels were upregulated in gills, head kidney, and blood cells following experimental immune stimulation. Recombinant AcLysC exhibited potent lytic activity against Vibrio anguillarum, whereas recombinant AcLysG-like showed remarkable antibacterial activity against Vibrio harveyi and Streptococcus parauberis, which was further evidenced by scanning electron microscopic imaging of destructed bacterial cell walls. The findings of this study collectively suggest the potential roles of AcLysC and AcLysG-like in host immune defense.

• Nuclear Engineering and Technology
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• v.54 no.12
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• pp.4514-4521
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• 2022

In this study, the effects of heat and radiation on the degradation behaviour of fluoroelastomer under simulated normal operation and a severe accident environment were investigated using sequential testing of gamma irradiation and thermal degradation. Tensile properties and Shore A hardness were measured, and thermogravimetric analysis was used to evaluate the degradation behaviour of fluoroelastomer. Fourier transform infrared spectroscopy and X-ray photoelectron spectroscopy were used to characterize the structural changes of the fluoroelastomer. Heat and radiation generated in nuclear power plant break and deform the chemical bonds, and fluoroelastomer exposed to these environments have decreased C-H and functional groups that contain oxygen and double bonds such as C-O, C=O and C=C were generated. These functional groups were formed by auto oxidation by reacting free radicals generated from the cleaved bond with oxygen in the atmosphere. In this auto oxidation reaction, crosslinks were generated where bonded to each other, and the mobility of molecules was decreased, and as a result, the fluoroelastomer was hardened. This hardening behaviour occurred more significantly in the severe accident environment than in the normal operation condition, and it was found that thermal stability decreased with the generation of unstable structures by crosslinking.

• Journal of the Korea Society of Computer and Information
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• v.14 no.12
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• pp.139-145
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• 2009

This study proposes a model of collection process for real-time forensic data, in which the manager was to respond to infringement incidents in terms of system operation and inspection and to collect, analyze and restore forensic data immediately after an incident took place. The suggested model was modeled in seven processes according to functional elements. Unlike the old and managerial forensic processes, the model allowed the manager to react to infringement incidents in the aspects of system operation and inspection and to follow the processes of collecting, analyzing, and restoring forensic data in case of an incident. There also was a feedback process designed towards the step of gathering forensic data through the stages of systematizing reaction strategies in order that he or she be able to bring about comprehensive and structural responses to an incident like the former processes in which it is difficult to bring about instant responses.

• Journal of Korean Tunnelling and Underground Space Association
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• v.12 no.2
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• pp.157-164
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• 2010

Recently, the number of shallow tunnel construction increases to improve the structural safety and environment-friendliness. In semi-cut-and-cover Method, ground is excavated to the crown arch level and arch slab is set to backfill before the excavation of lower face. In this study, laboratory model tests was performed to clarify the behavior of the arch slab constructed perpendicular to the slope. Results show that Arch slab is affected by perpendicular to the slope and bedrocks. Negative moment at the upper part of the arch slab at hillside and positive moment at the upper part at the other side are generated as perpendicular to the slope increases. Reaction load at the hillside support was larger than that at the other side.

• The Journal of the Convergence on Culture Technology
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• v.9 no.4
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• pp.503-508
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• 2023

Tryptane derivatives are substances that treat acute migraines, and many studies have been conducted on analysis methods such as chromatography, electrochemistry, spectroscopy, and capillary electrophysiology. Recently, analytical chemists have become more interested in drug analysis and solving fundamental problems of biological importance. Therefore, in this study, the chemical properties of each derivative were investigated by calculating the total energy, band gap, electrostatic potential, and charge of Sumatriptan, Lizatriptan, Naratriptan, and Eletriptan using HyperChem8.0's semi-empirical PM3 method. As a result of this study, in the case of Sumatriptan, Naratriptan, and Eletriptan, chemical reactions are expected to proceed centering on oxygen and nitrogen atoms bonded to sulfur atoms. In addition, in the case of Rizatriptan without a sulfur atom, it was shown that the chemical reaction proceeds at the 17th and 19th nitrogens of the 5-membered heterocyclic compound.

• Journal of Microbiology and Biotechnology
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• v.33 no.10
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• pp.1351-1360
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• 2023

Endocrine-disrupting chemicals (EDCs) are compounds that disturb hormonal homeostasis by binding to receptors. EDCs are metabolized through hepatic enzymes, causing altered transcriptional activities of hormone receptors, and thus necessitating the exploration of the potential endocrine-disrupting activities of EDC-derived metabolites. Accordingly, we have developed an integrative workflow for evaluating the post-metabolic activity of potential hazardous compounds. The system facilitates the identification of metabolites that exert hormonal disruption through the integrative application of an MS/MS similarity network and predictive biotransformation based on known hepatic enzymatic reactions. As proof-of-concept, the transcriptional activities of 13 chemicals were evaluated by applying the in vitro metabolic module (S9 fraction). Identified among the tested chemicals were three thyroid hormone receptor (THR) agonistic compounds that showed increased transcriptional activities after phase I+II reactions (T3, 309.1 ± 17.3%; DITPA, 30.7 ± 1.8%; GC-1, 160.6 ± 8.6% to the corresponding parents). The metabolic profiles of these three compounds showed common biotransformation patterns, particularly in the phase II reactions (glucuronide conjugation, sulfation, GSH conjugation, and amino acid conjugation). Data-dependent exploration based on molecular network analysis of T3 profiles revealed that lipids and lipid-like molecules were the most enriched biotransformants. The subsequent subnetwork analysis proposed 14 additional features, including T4 in addition to 9 metabolized compounds that were annotated by prediction system based on possible hepatic enzymatic reaction. The other 10 THR agonistic negative compounds showed unique biotransformation patterns according to structural commonality, which corresponded to previous in vivo studies. Our evaluation system demonstrated highly predictive and accurate performance in determining the potential thyroid-disrupting activity of EDC-derived metabolites and for proposing novel biotransformants.